Jackfruit Plant – unusual behaviour
I've had a few problems with my jackfruit plant for a few months but recently its got worse and I'm afraid it may die. I am growing it for ornamental reasons in a plant pot since I live in the uk where the climate is too cold for jackfruit. I started growing it 2 years ago. About 4 months ago all the leaves started turning yellow and falling off, but at the same time the plant was rapidly growing branches with new leaves so this eased my corncern somewhat. Then the new leaves started getting white spots and falling off within a week of the plant sending them out, eventually this settled down but the leaves still don't last very long, they fall of within weeks and leaf production has slowed. The next problem was with tiny black flies in the soil. During this time it was moved from kitchen window where it had been for its entire existence to the floor in the dining room. Someone told me to use garlic water to get rid of them- which was useless- in the end I removed the fly infested soil and topped it up with citrus compost that someone from a garden centre recommended and moved it back to the kitchen window. This was done a month ago and the plant has only produced 2 very tiny new leaves whilst 4 leaves fell off green. All of the remaining leaves apart from the newest 2 have brown markings on them as well. I have attached some photos to help. Please help me.
I believe this all stemmed from an accidental over-watering incident. It appears that a bacterial or fungal infection has set in. The best thing would be to change the soil again, but this time add a little wettable sulfur and dolomitic lime into the mix. This will curb any future infection, as well as help treat the current one.
The soil should remain slightly moist. Not overly wet, or dry. Let the first two inches of soil dry before watering again. You can check this by putting your finger in, and feeling for the moisture.
Here is an article for more information on care of the tree: https://www.gardeningknowhow.com/edible/fruits/jackfruit-trees/growing-jackfruit-trees.htm